The present invention relates to a solar house, and more specifically to a roofing for the solar house provided with a solar battery.
The use of solar batteries as a clean energy power supply source has been greatly anticipated. Since the output power of a solar battery is proportional to its surface area, a large installation area is required for obtaining a large electric power. An upper surface of a house, particularly a slant roof, which is not usually utilized for living but is close to a power consumption point, is suitable for installing the solar battery.
The simplest method to install the solar battery on the roof is to fix a mount to the roof members by fixtures and to put modules of the solar battery formed of multiple solar cells on the mount. The mount and the battery module form independent structures, which require structural strength and spoil the beauty of the house.
To solve the problem described above, it has been heretofore proposed to incorporate the solar cells into roof tiles, or to form the solar cells on an underlayer and covering the solar cells with a transparent encapsulating material.
FIGS. 2 and 3 are an example showing roofing elements in which the solar cells are placed on the underlayers. As shown in FIG. 2, the roofing elements 21, on the surface of which the solar cells are arranged, are placed on roof boards 22, and held in place with crosspieces 23 spaced apart from each other at a predetermined distance Reinforced-glass tiles are placed onto the roofing elements as finishing overlayers 24, which are further secured with fixing means 25 (FIG. 3).
In the roof shown in FIGS. 2 and 3, the crosspieces 23 shade the roofing elements 21 and thus reduce generation of the photovoltaic current by the shaded areas of the solar cells. When solar cells of nearly the same photovoltaic characteristics are connected in series, if the current generated by some of the solar cells is reduced, the total current is limited by the reduced current. As a result, the overall output is greatly reduced. The same problem also occurs by mounting the solar cells on the finishing overlayers, covering their surfaces with transparent weatherproof layers, and fixing them with the crosspieces.
The object of the present invention is to solve the problem described above and to provide a solar battery roofing for a solar house, wherein the reduction of the output of the solar cells due to shadowing by the crosspieces for fixing the roofing with the solar battery elements is minimized.